size_t vterm_input_write(VTerm *vt, const char *bytes, size_t len)
{
size_t pos = 0;
const char *string_start;
switch(vt->parser.state) {
case NORMAL:
case CSI_LEADER:
case CSI_ARGS:
case CSI_INTERMED:
case ESC:
string_start = NULL;
break;
case STRING:
case ESC_IN_STRING:
string_start = bytes;
break;
}
#define ENTER_STRING_STATE(st) do { vt->parser.state = STRING; string_start = bytes + pos + 1; } while(0)
#define ENTER_STATE(st) do { vt->parser.state = st; string_start = NULL; } while(0)
#define ENTER_NORMAL_STATE() ENTER_STATE(NORMAL)
for( ; pos < len; pos++) {
unsigned char c = bytes[pos];
if(c == 0x00 || c == 0x7f) { // NUL, DEL
if(vt->parser.state >= STRING) {
more_string(vt, string_start, bytes + pos - string_start);
string_start = bytes + pos + 1;
}
continue;
}
if(c == 0x18 || c == 0x1a) { // CAN, SUB
ENTER_NORMAL_STATE();
continue;
}
else if(c == 0x1b) { // ESC
vt->parser.intermedlen = 0;
if(vt->parser.state == STRING)
vt->parser.state = ESC_IN_STRING;
else
ENTER_STATE(ESC);
continue;
}
else if(c == 0x07 && // BEL, can stand for ST in OSC or DCS state
vt->parser.state == STRING) {
// fallthrough
}
else if(c < 0x20) { // other C0
if(vt->parser.state >= STRING)
more_string(vt, string_start, bytes + pos - string_start);
do_control(vt, c);
if(vt->parser.state >= STRING)
string_start = bytes + pos + 1;
continue;
}
// else fallthrough
switch(vt->parser.state) {
case ESC_IN_STRING:
if(c == 0x5c) { // ST
vt->parser.state = STRING;
done_string(vt, string_start, bytes + pos - string_start - 1);
ENTER_NORMAL_STATE();
break;
}
vt->parser.state = ESC;
// else fallthrough
case ESC:
switch(c) {
case 0x50: // DCS
start_string(vt, VTERM_PARSER_DCS);
ENTER_STRING_STATE();
break;
case 0x5b: // CSI
vt->parser.csi_leaderlen = 0;
ENTER_STATE(CSI_LEADER);
break;
case 0x5d: // OSC
start_string(vt, VTERM_PARSER_OSC);
ENTER_STRING_STATE();
break;
default:
if(is_intermed(c)) {
if(vt->parser.intermedlen < INTERMED_MAX-1)
vt->parser.intermed[vt->parser.intermedlen++] = c;
}
else if(!vt->parser.intermedlen && c >= 0x40 && c < 0x60) {
do_control(vt, c + 0x40);
ENTER_NORMAL_STATE();
}
else if(c >= 0x30 && c < 0x7f) {
do_escape(vt, c);
ENTER_NORMAL_STATE();
}
else {
DEBUG_LOG("TODO: Unhandled byte %02x in Escape\n", c);
}
}
break;
case CSI_LEADER:
/* Extract leader bytes 0x3c to 0x3f */
if(c >= 0x3c && c <= 0x3f) {
if(vt->parser.csi_leaderlen < CSI_LEADER_MAX-1)
vt->parser.csi_leader[vt->parser.csi_leaderlen++] = c;
break;
}
/* else fallthrough */
vt->parser.csi_leader[vt->parser.csi_leaderlen] = 0;
vt->parser.csi_argi = 0;
vt->parser.csi_args[0] = CSI_ARG_MISSING;
vt->parser.state = CSI_ARGS;
/* fallthrough */
case CSI_ARGS:
/* Numerical value of argument */
if(c >= '0' && c <= '9') {
if(vt->parser.csi_args[vt->parser.csi_argi] == CSI_ARG_MISSING)
vt->parser.csi_args[vt->parser.csi_argi] = 0;
vt->parser.csi_args[vt->parser.csi_argi] *= 10;
vt->parser.csi_args[vt->parser.csi_argi] += c - '0';
break;
}
if(c == ':') {
vt->parser.csi_args[vt->parser.csi_argi] |= CSI_ARG_FLAG_MORE;
c = ';';
}
if(c == ';') {
vt->parser.csi_argi++;
vt->parser.csi_args[vt->parser.csi_argi] = CSI_ARG_MISSING;
break;
}
/* else fallthrough */
vt->parser.csi_argi++;
vt->parser.intermedlen = 0;
vt->parser.state = CSI_INTERMED;
case CSI_INTERMED:
if(is_intermed(c)) {
if(vt->parser.intermedlen < INTERMED_MAX-1)
vt->parser.intermed[vt->parser.intermedlen++] = c;
break;
}
else if(c == 0x1b) {
/* ESC in CSI cancels */
}
else if(c >= 0x40 && c <= 0x7e) {
vt->parser.intermed[vt->parser.intermedlen] = 0;
do_csi(vt, c);
}
/* else was invalid CSI */
ENTER_NORMAL_STATE();
break;
case STRING:
if(c == 0x07 || (c == 0x9c && !vt->mode.utf8)) {
done_string(vt, string_start, bytes + pos - string_start);
ENTER_NORMAL_STATE();
}
break;
case NORMAL:
if(c >= 0x80 && c < 0xa0 && !vt->mode.utf8) {
switch(c) {
case 0x90: // DCS
start_string(vt, VTERM_PARSER_DCS);
ENTER_STRING_STATE();
break;
case 0x9b: // CSI
ENTER_STATE(CSI_LEADER);
break;
case 0x9d: // OSC
start_string(vt, VTERM_PARSER_OSC);
ENTER_STRING_STATE();
break;
default:
do_control(vt, c);
break;
}
}
else {
size_t eaten = 0;
if(vt->parser.callbacks && vt->parser.callbacks->text)
eaten = (*vt->parser.callbacks->text)(bytes + pos, len - pos, vt->parser.cbdata);
if(!eaten) {
DEBUG_LOG("libvterm: Text callback did not consume any input\n");
/* force it to make progress */
eaten = 1;
}
pos += (eaten - 1); // we'll ++ it again in a moment
}
break;
}
}
return len;
}
void vterm_push_bytes(VTerm *vt, const char *bytes, size_t len)
{
size_t pos = 0;
const char *string_start;
switch(vt->parser_state) {
case NORMAL:
string_start = NULL;
break;
case ESC:
case ESC_IN_OSC:
case ESC_IN_DCS:
case CSI:
case OSC:
case DCS:
string_start = bytes;
break;
}
#define ENTER_STRING_STATE(st) do { vt->parser_state = st; string_start = bytes + pos + 1; } while(0)
#define ENTER_NORMAL_STATE() do { vt->parser_state = NORMAL; string_start = NULL; } while(0)
for( ; pos < len; pos++) {
unsigned char c = bytes[pos];
if(c == 0x00 || c == 0x7f) { // NUL, DEL
if(vt->parser_state != NORMAL) {
append_strbuffer(vt, string_start, bytes + pos - string_start);
string_start = bytes + pos + 1;
}
continue;
}
if(c == 0x18 || c == 0x1a) { // CAN, SUB
ENTER_NORMAL_STATE();
continue;
}
else if(c == 0x1b) { // ESC
if(vt->parser_state == OSC)
vt->parser_state = ESC_IN_OSC;
else if(vt->parser_state == DCS)
vt->parser_state = ESC_IN_DCS;
else
ENTER_STRING_STATE(ESC);
continue;
}
else if(c == 0x07 && // BEL, can stand for ST in OSC or DCS state
(vt->parser_state == OSC || vt->parser_state == DCS)) {
// fallthrough
}
else if(c < 0x20) { // other C0
if(vt->parser_state != NORMAL)
append_strbuffer(vt, string_start, bytes + pos - string_start);
do_control(vt, c);
if(vt->parser_state != NORMAL)
string_start = bytes + pos + 1;
continue;
}
// else fallthrough
switch(vt->parser_state) {
case ESC_IN_OSC:
case ESC_IN_DCS:
if(c == 0x5c) { // ST
switch(vt->parser_state) {
case ESC_IN_OSC: vt->parser_state = OSC; break;
case ESC_IN_DCS: vt->parser_state = DCS; break;
default: break;
}
do_string(vt, string_start, bytes + pos - string_start - 1);
ENTER_NORMAL_STATE();
break;
}
vt->parser_state = ESC;
string_start = bytes + pos;
// else fallthrough
case ESC:
switch(c) {
case 0x50: // DCS
ENTER_STRING_STATE(DCS);
break;
case 0x5b: // CSI
ENTER_STRING_STATE(CSI);
break;
case 0x5d: // OSC
ENTER_STRING_STATE(OSC);
break;
default:
if(c >= 0x30 && c < 0x7f) {
/* +1 to pos because we want to include this command byte as well */
do_string(vt, string_start, bytes + pos - string_start + 1);
ENTER_NORMAL_STATE();
}
else if(c >= 0x20 && c < 0x30) {
/* intermediate byte */
}
else {
fprintf(stderr, "TODO: Unhandled byte %02x in Escape\n", c);
}
}
break;
case CSI:
if(c >= 0x40 && c <= 0x7f) {
/* +1 to pos because we want to include this command byte as well */
do_string(vt, string_start, bytes + pos - string_start + 1);
ENTER_NORMAL_STATE();
}
break;
case OSC:
case DCS:
if(c == 0x07 || (c == 0x9c && !vt->is_utf8)) {
do_string(vt, string_start, bytes + pos - string_start);
ENTER_NORMAL_STATE();
}
break;
case NORMAL:
if(c >= 0x80 && c < 0xa0 && !vt->is_utf8) {
switch(c) {
case 0x90: // DCS
ENTER_STRING_STATE(DCS);
break;
case 0x9b: // CSI
ENTER_STRING_STATE(CSI);
break;
case 0x9d: // OSC
ENTER_STRING_STATE(OSC);
break;
default:
do_control(vt, c);
break;
}
}
else {
size_t text_eaten = do_string(vt, bytes + pos, len - pos);
if(text_eaten == 0) {
string_start = bytes + pos;
goto pause;
}
pos += (text_eaten - 1); // we'll ++ it again in a moment
}
break;
}
}
pause:
if(string_start && string_start < len + bytes) {
size_t remaining = len - (string_start - bytes);
append_strbuffer(vt, string_start, remaining);
}
}